Mixing equipment



Qct- 9. 1956 c. E. BENDER 2,766,022

MIXING. EQUIPMENT Filed June 3, 1954 INVENTbR flag/ Z 36%6/61' ATTORNEY nited dtates Patented Oct. 9, 1956 MEXING EQUIPMENT Charles E. Bender, Hastings on Hudson, N. Y., assignor to Virtis Company, Incorporated, Yonkers, N. Y., a corporation of New York Application June 3, 195 4, Serial No. 434,200 3 Claims. (Cl. 259-422) This invention relates to mixing equipment, particularly high speed mixers. It is directed at the problem of controlling atomization, and aims to provide an apparatus for high speed mixing in which aerosols from the fluid are prevented from leaving the mixing vessel.

Any mixing of any fluid disturbs the surface, and some mist is formed by this disturbance. As speed goes up, disturbance and consequent atomization or misting increases. For example, even the relatively slow speeds used in whipping cream on a household mixer can throw cream far out of the bowl. When speeds of 20,000 or more R. P. M. are used, as in the case of homogenization of biologicals, misting becomes a serious problem. If the liquid is at all dangerous, the homogenization must be done in a completely closed system, which may be expensive, or diificult to clean and/or sterilize, or have some other disadvantage. A simple high speed stirring device in a container cannot be used, because the mist escapes through the hole in the container lid through which the stirrer passes.

I have discovered that escape of mist can be prevented from passing inward and upward to the hole in the lid.

Most preferably, for handling dangerous biologicals, the lid has downwardly projecting baffles which mesh with upwardly projecting bafiies on the disc, to add a safety element to the assemblage. The baffled devices can be used for high speed homogenization, even at speeds of the order of 40,000 R. P. M., with no trace of atmospheric contamination.

The drawings disclose a invention; in the drawings,

Fig. l is a section to a vention mounted thereon,

Fig. 2 is a plan view of the lid used in Fig. 1,

Fig. 3 is a plan view of the sealing disc used in Fig. 1.

Referring to the drawings, the container 10, preferably of glass, has mounted thereon a lid 11. It consists of a flat disc 12 of Teflon or other material; a hole 13 is provided to permit a mixer shaft 14 to pass through. Down- Wardly projecting rings 15 and 16 are located at the edge of the disc; they form a channel 17 which tightly fits the upper rim of the container 10. Similar downwardly projecting bafiie rings 18 and 19 are located between the hole 13 and the edge rings 15 and 16.

The bottom piece 20 consists of a flat disc 21 of Teflon or similar flexible material; hole 22 is provided which preferred embodiment of the high speed mixer, with my inthe rod. An upwardly extendlng edge baflie ring 23 fits between rings 17 and 18 on the lid piece; a central baffle ring 24 fits between the rings 18 and 19. In practice, the

ring 20 is mounted on the stirrer just below the lid, so that the baifies overlap as shown.

Teflon (poly tetrachlorodifiuoroethylene) is one of the preferred materials solvents, acids and sterilized at the high tembiological work. Other materials can alkalis, and in addition can be peratures used for but single baffled piece have proved effective even at such high speeds as 40,000 R. P. M.

a stirrer, a baflied lid, and a the lid-sealing is obtained by Cleaning and sterilization are very can be changed without dewhich is defined in the claims.

' central hole therein; a stirrer shaft passing through the container to retard through the hole in the center of the lid.

2. The apparatus of claim 1, in which the lid carries a pair of downwardly extending projections about its rim which clamp the rim of the container top tightly between them.

References Cited in the file of this patent UNITED STATES PATENTS 

